diff --git a/src/flexible.js b/src/flexible.js
index 4e7c545..1b4c87c 100644
--- a/src/flexible.js
+++ b/src/flexible.js
@@ -37,9 +37,9 @@
         var devicePixelRatio = win.devicePixelRatio;
         if (isIPhone) {
             // iOS下，对于2和3的屏，用2倍的方案，其余的用1倍方案
-            if (devicePixelRatio >= 3 && (!dpr || dpr >= 3)) {                
+            if (devicePixelRatio >= 3) {                
                 dpr = 3;
-            } else if (devicePixelRatio >= 2 && (!dpr || dpr >= 2)){
+            } else if (devicePixelRatio >= 2){
                 dpr = 2;
             } else {
                 dpr = 1;
@@ -114,4 +114,4 @@
         return val;
     }
 
-})(window, window['lib'] || (window['lib'] = {}));
\ No newline at end of file
+})(window, window['lib'] || (window['lib'] = {}));